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只听写例句。前面的单词不用听写。注意有一对引号。
这一期有两个例句哦。Sometimes the muscle is not attached directly to the bone but to a tough, nonstretchable cord, or tendon, that is attached to the bone.
Often called "the wanderer", it is tough and powerful as butterflies go, and is capable of long flights at speeds of 20 miles per hour or more.